This invention relates to electrical equipment.
The invention is more particularly concerned with equipment for testing operation of electrical igniters.
To test correct functioning of an igniter, and especially an igniter for a gas-turbine engine, a measure is taken of the minimum voltage at which the igniter fires for a prescribed number of times in succession. This is done in practice by manually setting the value of a voltage source which may be of various different constructions. The voltage source produces a voltage pulse across the igniter and, if it does not fire, the operator sets the voltage to a higher value and the procedure is repeated. When the igniter does fire, the procedure is repeated at the same voltage and, if the igniter fires again, and does this five times in succession, this is deemed to be the igniter onset voltage. If, however, the igniter fails to fire five times, the voltage must be increased again until this does happen.
This is a relatively lengthy procedure and the provision of suitable equipment capable of producing a high voltage pulse of adjustable value has presented various difficulties.